foo.cc: In function ‘int main()’:
foo.cc:7:19: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
    7 |         if(y%4==0 && y%100!=0 || y%400==0)
      |            ~~~~~~~^~~~~~~~~~~
foo.cc:16:21: warning: suggest parentheses around comparison in operand of ‘|’ [-Wparentheses]
   16 |                 if(m==1 |m==3 ||m==5 ||m==7 ||m==8 ||m==10 ||m==12 )
      |                    ~^~~
foo.cc:24:21: warning: suggest parentheses around comparison in operand of ‘|’ [-Wparentheses]
   24 |                 if(m==4 |m==6 ||m==9 ||m==11)
      |                    ~^~~
foo.cc:53:21: warning: suggest parentheses around comparison in operand of ‘|’ [-Wparentheses]
   53 |                 if(m==1 |m==3 ||m==5 ||m==7 ||m==8 ||m==10 ||m==12 )
      |                    ~^~~
foo.cc:61:21: warning: suggest parentheses around comparison in operand of ‘|’ [-Wparentheses]
   61 |                 if(m==4 |m==6 ||m==9 ||m==11)
      |                    ~^~~